I want to restore a previously backed up SQL DB for QC Project. The original bkp was created using QC 9.0
The version I try to restore is QC 9.2

The steps I follow are
1) Create a new project in Quality Center
2) Go to SQL Enterprise manager and for the same database try to restore the backup file
3) I get the error message 'Exclusive Access cannot be obtined because the database is in use'

There is no other users connected or using this database. How to resolve this problem?